Additives benzoic acid

Table 8.2 The influence of different process parameters on the nanostructure of aluminum deposits. In the case of additive addition benzoic acid was used.

Fig. 8.7 Cyclic voltammograms for aluminum deposition with increasing amounts of additive (benzoic acid) [74].

FIGURE 13-7. Effect of pH on the retention times of the beverage additives , benzoic acid , aspartame , caffeine o, saccharin. Conditions are the same as Figure 13-6 with the pH of the acetic-acid component adjusted with 50% sodium hydroxide to the desired pH. (Note Actual separation will depend upon the quality of the mobile phase and column packing.) (Reproduced from reference 6 with permission.)... 

Another example of catalytic alkenation of carbonyl compounds such as acetophenone with ethyl diazoacetate catalyzed by Fe(TPP)Cl in the presence of an additive benzoic acid yielded a mixture of Z/ -alkenes 4.111 in 59 41 ratio in 84% yield. 

Figure 3.38 Disruption of crystal growth process by the incorporation of tailor-made additive benzoic acid at the interface of a growing benzamide crystal. (After Wright 1987.)...

Simultaneous Spectrophotometric Determination of Food Additives (Benzoic Acid, Caffeine, Aspartame and Acesulfame-K) in Cola Drinks by PLS Multivariate Calibration Method... 

Benzhydrazide added slowly at room temp, to 2.5 moles Pb-tetraacetate in benzene, and the product isolated when Ng-evolution ceases within 2 min. after the final addition benzoic acid. Y 90%. Also with mercuric acetate and f. e. s. J. B. Aylward and R. O. C. Norman, Soc. (C) 1968, 2399 with coned. HCl-acetic acid s. S. O. Yurzhenko and M. M. Turkevidi, Dopov Akad. Nauk Ukr. RSR, Sen B. SO, 743 (1968) C. A. 70, 47351. 

The main field of application for benzoic acid is the production of phenol however, the significance of this phenol route has declined in recent years. Additionally, benzoic acid is used in the production of benzoyl chloride and sodium benzoate. In Italy, benzoic acid is used as the raw material for the production of 8-caprolactam, in a process developed by Snia Viscosa, This involves hydrogenating benzoic add at 170 °C and 15 bar over a palladium catalyst, purifying the cyclohexane carboxylic acid by distillation followed by its reaction with nitrosyl-sulfuric acid to yield 8-caprolactam. 

FAO/WHO. 2007b. Expert Committee of Food Additives Benzoic Acid. Available www.inchem.org/documents/jecfa/jeceval/jec 184.htm (accessed June 27, 2007). 

It is readily oxidized by air to benzoic acid. With aqueous KOH gives benzyl alcohol and benzoic acid. Gives addition products with hydrogen cyanide and sodium hydrogen sulphite. 

Prepare a mixture of 30 ml, of aniline, 8 g. of o-chloro-benzoic acid, 8 g. of anhydrous potassium carbonate and 0 4 g. of copper oxide in a 500 ml. round-bottomed flask fitted with an air-condenser, and then boil the mixture under reflux for 1 5 hours the mixture tends to foam during the earlier part of the heating owing to the evolution of carbon dioxide, and hence the large flask is used. When the heating has been completed, fit the flask with a steam-distillation head, and stcam-distil the crude product until all the excess of aniline has been removed. The residual solution now contains the potassium. V-phenylanthrani-late add ca. 2 g. of animal charcoal to this solution, boil for about 5 minutes, and filter hot. Add dilute hydrochloric acid (1 1 by volume) to the filtrate until no further precipitation occurs, and then cool in ice-water with stirring. Filter otT the. V-phcnylanthranilic acid at the pump, wash with water, drain and dry. Yield, 9-9 5 g. I he acid may be recrystallised from aqueous ethanol, or methylated spirit, with addition of charcoal if necessary, and is obtained as colourless crystals, m.p. 185-186°. 

If the benzoyl derivative is soluble in alkali, precipitate it together with the benzoic acid derived from the reagent by the addition of hydrochloric acid filter and extract the product with cold ether or light petroleum (b.p. 40-60°) to remove the benzoic acid. 

The kinetics of nitration of benzene in solutions at c. 20 °C in carbon tetrachloride have been investigated. In the presence of an excess of benzene (c. 2-4 mol 1 ) the rate was kinetically of the first order in the concentration of benzoyl nitrate. The rate of reaction was depressed by the addition of benzoic anhydride, provided that some benzoic acid was present. This result suggested that benzoyl nitrate itself was not responsible for the nitration, but generated dinitrogen pentoxide... 

Benzoic acid and naphthoic acid are formed by the oxidative carbonylation by use of Pd(OAc)2 in AcOH. t-Bu02H and allyl chloride are used as reoxidants. Addition of phenanthroline gives a favorable effect[360], Furan and thiophene are also carbonylated selectively at the 2-position[361,362]. fndole-3-carboxylic acid is prepared by the carboxylation of 1-acetylindole using Pd(OAc)2 and peroxodisulfate (Na2S208)[362aj. Benzoic acid derivatives are obtained by the reaction of benzene derivatives with sodium palladium mal-onate in refluxing AcOH[363]. 

The benzoic acid derivative 457 is formed by the carbonylation of iodoben-zene in aqueous DMF (1 1) without using a phosphine ligand at room temperature and 1 atm[311]. As optimum conditions for the technical synthesis of the anthranilic acid derivative 458, it has been found that A-acetyl protection, which has a chelating effect, is important[312]. Phase-transfer catalysis is combined with the Pd-catalyzed carbonylation of halides[3l3]. Carbonylation of 1,1-dibromoalkenes in the presence of a phase-transfer catalyst gives the gem-inal dicarboxylic acid 459. Use of a polar solvent is important[314]. Interestingly, addition of trimethylsilyl chloride (2 equiv.) increased yield of the lactone 460 remarkabiy[3l5]. Formate esters as a CO source and NaOR are used for the carbonylation of aryl iodides under a nitrogen atmosphere without using CO[316]. Chlorobenzene coordinated by Cr(CO)j is carbonylated with ethyl formate[3l7]. 

Styrene undergoes many reactions of an unsaturated compound, such as addition, and of an aromatic compound, such as substitution (2,8). It reacts with various oxidising agents to form styrene oxide, ben2aldehyde, benzoic acid, and other oxygenated compounds. It reacts with benzene on an acidic catalyst to form diphenylethane. Further dehydrogenation of styrene to phenylacetylene is unfavorable even at the high temperature of 600°C, but a concentration of about 50 ppm of phenylacetylene is usually seen in the commercial styrene product. 

Hydroxy group containing tertiary amines are also used because they become incorporated into the polymer stmcture, which eliminates odor formation ia the foam (3). Delayed-action or heat-activated catalysts are of particular interest ia molded foam appHcations. These catalysts show low activity at room temperature but become active when the exotherm builds up. In addition to the phenol salt of DBU (4), benzoic acid salts of Dabco are also used (5). 

In addition to the acid—base components shown in Figure 9, various organic acids are often found. Many of these acids are by-products of the atmospheric oxidation of organic matter released into the atmosphere. Of special interest are formic, acetic, oxaUc, and benzoic acids, which have been found in rainwater in concentrations occasionally exceeding a few micromoles per Hter. 

In addition to the presence of organic trace impurities, the color and color stabiUty of the benzoic acid are often important to customers. Various techniques are utilized to improve color and color stabiUty. Most if not all of these are considered trade secrets. 

Benzoic acid is also used as a down-hole drilling mud additive where it functions as a temporary plugging agent in subterranean formations. Since this is a secondary oil recovery appHcation, this use is heavily dependent on the price of cmde oil. 

Benzoic acid is suppHed to this market in the form of salts because the benzoate salts have a high solubiUty in water and aqueous stock solutions of up to 35% can easily be prepared. In addition, it is easier, and therefore cheaper, to purify sodium and potassium benzoate than to produce the USP/FCC grade of benzoic acid. 

Physical and Chemical Properties. The (F)- and (Z)-isomers of cinnamaldehyde are both known. (F)-Cinnamaldehyde [14371-10-9] is generally produced commercially and its properties are given in Table 2. Cinnamaldehyde undergoes reactions that are typical of an a,P-unsaturated aromatic aldehyde. Slow oxidation to cinnamic acid is observed upon exposure to air. This process can be accelerated in the presence of transition-metal catalysts such as cobalt acetate (28). Under more vigorous conditions with either nitric or chromic acid, cleavage at the double bond occurs to afford benzoic acid. Epoxidation of cinnamaldehyde via a conjugate addition mechanism is observed upon treatment with a salt of /-butyl hydroperoxide (29). 

The reaction of 2-phenyl-l-azirine (201) with benzoic acid gaveN-benzoylphenacylamine (204) (67BCJ2938). The overall mechanism of the reaction involves initial protonation on nitrogen followed by addition of the nucleophile to the azirinium ion and finally ring opening. 

Benzoic acid CgHjCOjH Alkyl resins, chemical intermediate, oil drilling additive, medicines... 

The ortho effect may consist of several components. The normal electronic effect may receive contributions from inductive and resonance factors, just as with tneta and para substituents. There may also be a proximity or field electronic effect that operates directly between the substituent and the reaction site. In addition there may exist a true steric effect, as a result of the space-filling nature of the substituent (itself ultimately an electronic effect). Finally it is possible that non-covalent interactions, such as hydrogen bonding or charge transfer, may take place. The role of the solvent in both the initial state and the transition state may be different in the presence of ortho substitution. Many attempts have been made to separate these several effects. For example. Farthing and Nam defined an ortho substituent constant in the usual way by = log (K/K ) for the ionization of benzoic acids, postulating that includes both electronic and steric components. They assumed that the electronic portion of the ortho effect is identical to the para effect, writing CTe = o-p, and that the steric component is equal to the difference between the total effect and the electronic effect, or cts = cr — cte- They then used a multiple LFER to correlate data for orrAo-substituted reactants. 

The reaction of 1,2,4-triazine 4-oxides 55 with water in the presence of benzoyl chloride affords 3-hydroxy-1,2,4-triazines 78. The mechanism suggested for this reaction includes acylation of the substrate at the oxygen of the iV-oxide group, followed by the addition of water to the 1,2,4-tiiazinium cation and the autoaromatization of the (T -adducts with the elimination of benzoic acid. 

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